Climate Engineering Conference 2017: a CSO perspective

By Oli Munnion (Biofuelwatch)

The Climate Engineering Conference 2017 aimed to “bring together the research, policy, and civic communities to discuss the highly complex and interlinked ethical, social and technical issues related to climate engineering.” In practice, the conference represented a concerted effort to normalise geoengineering among researchers, scientists and policy-makers, focusing almost solely on the technical and engineering challenges, and neglecting the social and ethical aspects.

Civil society representation felt largely tokenistic, with an unapologetic promotion of various forms of geoengineering research throughout the 4 days of events. The conference highlighted just how urgent it is for civil society to reject geoengineering publicly, and to bring this clique of academics and policy-makers back in line with global thinking on the subject.

Speaking and presenting slots were dominated by men from countries in the global North, to the extent that at least one panel discussion was entirely populated by men from either the US or Europe. The lack of diversity amongst the presenters reflected just how problematic it is that research into geoengineering techniques that will affect everyone, and in the global South disproportionately, is largely taking place in countries responsible for the greatest historical contributions to climate change.

The dominant discourse from academics and researchers was that they didn’t want to geoengineer the climate, but that if other forms of mitigation fail (i.e. drastic emissions reductions), the world needs to know whether geoengineering can step in, and if so, how to use it. In the case of solar radiation management (SRM) research, academics want to “know now if it’s not going to work“, so that we know whether it can be relied upon in the future. And if it can’t be relied on, then we know that we really do have to seriously reduce emissions instead. Read more about why experiments of one type of geoengineering are unwise and unethical here.

There were also two distinct camps of geoengineers – the “solar radiation management” geoengineers, who come across as your stereotypical ‘mad scientists,’ and who really don’t want to live in a geoengineered world but just can’t stop themselves from researching it. And the “carbon dioxide removal” geoengineers, who don’t consider themselves geoengineers and scoff at the irresponsible ideas of the SRM camp. The similarity they share is the belief that “carbon dioxide removal” or “negative emissions,” through technologies such as “bioenergy with carbon capture and storage” and “direct air capture,” will be essential mitigation strategies if catastrophic climate change is to be avoided. The promotion of these seemingly more benign forms of geoengineering from this section of the scientific community is very dangerous as it gives governments and industry another excuse to delay making essential emissions reductions, even though the technologies don’t exist yet, and are unlikely ever to.

In summary, the conference tried to normalise geoengineering as a response to climate change, both as a mitigation strategy (alongside emissions reductions) and as a “fail safe” in the event of mitigation not working.

Geoengineering is an unjust and inequitable solution to climate change, especially when its research, governance and deployment are in the hands of those most responsible for it. Climate change is not an engineering problem, it is a symptom of the multiple, deep-rooted crises that pervade human societies and the planet. The promotion of geoengineering is therefore very much part of the problem, and not the solution.

Highlights of the conference: 

CEC17 press briefing (video), 10 October 2017, which set the tone for the conference and highlighted key narratives and areas for debate.

 

Speakers were David Keith, Professor of Applied Physics and Professor of Public Policy at Harvard University, Mark Lawrence, Scientific Director at the Institute for Advanced Sustainability Studies (IASS), Lili Fuhr, Head of the Ecology and Sustainable Development Department at the Heinrich Böll Foundation, Pablo Suarez, Associate Director for Research and Innovation at the Red Cross Red Crescent Climate Centre.

CSO-led Sessions: 

Linda Schneider from Heinrich Böll Foundation introduces delegates to the new Interactive Map of Geoengineering Experiments

A change of course: Radical emission reduction pathways to stay under 1.5°C

Climate change is not an engineering problem. There are many viable alternatives to bring our societies on a pathway towards 1.5°C without geoengineering. A technofix mentality and powerful vested interests prevent us from implementing them. This session will explore how we can change course for a climate-just future.

Linda Schneider – Heinrich Böll Foundation , Lili Fuhr – Heinrich Böll Foundation & ETC Group

Barbara Unmüßig – Heinrich Böll Foundation , Karin Nansen – Friends of the Earth International , Silvia Ribeiro – ETC Group , Uwe Leprich – German Federal Environment Agency , Bernd Nilles – Fastenopfer – Swiss Catholic Lenten Fund

Social Movements & Climate Engineering Justice from the Periphery

Debate around the justice of geoengineering has often, implicitly or explicitly, assumed the perspective of high-emitting groups that are disproportionately responsible for geoengineering research. We should re-orient our normative thinking regarding climate engineering research, governance, and deployment to include the agency and perspectives of the global South and subaltern groups. We will convene global representatives from diverse social movements to lead intersectional discussions on what geoengineering means for racial and environmental justice, food sovereignty, youth, gender, health and global justice as well as climate justice.

Patrick Taylor-Smith – National University Singapore , Jim Thomas – ETC Group , Duncan McLaren – Lancaster Environment Centre

David Morrow – American University & Forum for Climate Engineering Assessment , Aniruddh Mohan – Wuppertal Institute for Climate, Environment and Energy , Octavio Rosas-Landa – National University Mexico , Nnimmo Bassey – Health of Mother Earth Foundation (HOMEF)

 

 

New briefing: Why are Solar Radiation Management Experiments a Bad Idea?

by ETC Group.

A new briefing from ETC Group outlines the ethical, political and environmental arguments against solar radiation management (SRM), and explains why even SRM experiments are a bad idea. The backgrounder was released in late March 2017 after Harvard University announced they are planning open-air SRM experiments  in Arizona in 2018. Read the briefing and related materials at: http://www.etcgroup.org/content/why-srm-experiments-are-bad-idea

ETC Group also issued a news release and supporting materials explaining how the new US administration could “inflate geoengineers’ balloon” and create favourable circumstances for geoengineering experiments now and in the future.

Pulling carbon out of the air: NETS, BECCS, and CDR

ADM’s Agricultural Processing and Biofuels Plant, Decatur, IL. Credit: National Energy Technology Laboratory

Geoengineering Monitor has long reported on the speculative concept of “negative emissions”, together with certain favored approaches such as bioenergy with carbon capture and storage (BECCS) – a geoengineering technique which recent studies show would have significant negative impacts on biodiversity, food security, and livelihoods.

To get a better sense of the technologies under discussion, we sent a correspondent to a “Carbon Dioxide Removal / Negative Emissions Technologies (NETs)” workshop earlier this month, co-sponsored by fora associated with American University, University of California – Berkeley, and Arizona State University.

A primary theme of the workshop was understanding NETs in the context of the Paris Agreement. Katharine Mach, senior research scientist at Stanford University and director of the Stanford Environment Assessment Facility, opened the day by describing the “pledge, review, and revise” approach of the agreement, and singled out the key role envisioned for BECCS in the models that underpin its target to stay below 2 degrees C average global temperature rise.

Wil Burns, co-director of the Forum for Climate Engineering Assessment at American University, made the case that the agreement provides authorization for countries to use artificial carbon sinks (CDR and NETs) as part of their Paris pledges. Burns built his case off of the UN Framework Convention on Climate Change (UNFCCC)’s broad definition of mitigation, which includes not only emissions reductions, but also the enhancement of sinks.

However, insofar as they aim to deliberately increase carbon sequestration on a large scale that may affect biodiversity, all proposed artificial carbon sinks are geoengineering proposals – and therefore subject to a de facto moratorium under the UN Convention on Biological Diversity (CBD), most recently reaffirmed at the end of 2016. The CBD’s moratorium derives from the application of the precautionary principle, noting that the potential impacts of geoengineering on biodiversity and traditional livelihoods have been scarcely studied.

Ongoing discussions within the multilateral institutions will likely provide more clarity on the boundary between climate mitigation and geoengineering. But for the meantime, it appears clear that attempts to push CDR techniques through the mitigation loophole will run up against the CBD moratorium. And judging by the other panels at the Berkeley CDR / NETs workshop, that’s probably a good thing.

Outside of the lively debate on BECCS – the star child of CDR advocates – the other approaches on offer ranged from relatively mundane reflections about enhancing rocks and protecting forests, to more fantastical proposals for offshore kelp-platforms riding ocean thermals. The general feel was that of an oddball trade show, with subsequent presenters arising to pitch their particular techno-fix, all seemingly underlaid by a dark acknowledgement of the social and political realities preventing meaningful climate action.

Daniel Sanchez, a postdoc at Stanford University’s Carnegie Institution for Science, kicked off the BECCS panel with a detailed technical and economic assessment of deployment possibilities, making the case that BECCS could enable a carbon-negative power system in western North America by mid-century, given a stringent emissions cap. Interestingly, Sanchez noted that the primary value of BECCS lies in its capacity to function as an offset, and less so as a source of electricity.

This point was addressed indirectly by Daniel Babson, technology manager at the Bioenergy Technologies Office within the Department of Energy (DOE). Babson asked attendees to “imagine BECCS in a world with cheap CO2 and cheap energy,” noting that the Trump administration has upended assumptions about an inevitable national carbon price or cap leading to a more competitive position for future bioenergy deployment. Babson’s prognosis on whether BECCS could flourish without a price on carbon wasn’t particularly sunny, and he noted that the DOE was reorienting towards near-term carbon sequestration via value-added products, such as wood for use in buildings or infrastructure.

Babson also referenced another way in which the new administration is a setback for BECCS. US government funding for carbon-negative bioenergy R&D falls squarely between the Office of Fossil Energy and the Office of Energy Efficiency and Renewable Energy – both of which are reportedly on the chopping block in the Trump administration’s proposed budget. If the Trump administration is successful in dismantling these offices, Babson will not only be out of a job (as he wryly joked), but BECCS proponents will have lost a critical source of funding and research.

Tim Searchinger, a research scholar at Princeton University and senior fellow at World Resource Institute, functioned as the black sheep of the panel discussion, making the case that studies showing large bioenergy emissions reductions potential are based on double-counting emissions reductions due to plant growth, and that replacing fossil fuels with bioenergy could actually increase GHG emissions, in addition to having major impacts on biodiversity and food security.

Searchinger asserted that so-called marginal or abandoned lands proposed for bioenergy feedstocks are largely already in use by local communities, or required by ecosystems to stay healthy. Margaret Torn, co-director of the Climate and Carbon Sciences Program at Lawrence Berkeley National Laboratory, also raised questions about the ecological limits to bioenergy expansion, focusing on land and resource requirements such as nitrogen and phosphorus. Searchinger made the case that using all of the world’s current harvested biomass would only meet one fifth of the world’s energy needs in 2050, in the process displacing communities and undermining biodiversity.

The final speaker of the day was Janos Pasztor, former senior advisor on climate to the UN secretary general, and recently appointed as director of the new Carnegie Climate Geoengineering Governance Project.

Pazstor, fresh off a meeting with California governor Jerry Brown, introduced the new “C2G2” project as a response to the need for systematic governance frameworks to guide geoengineering research and potential deployment. The aim of the project, according to Pazstor, is to engage with non-governmental organizations, governments, and other groups to build a network of people who could feed into future governance mechanisms.

While building out a coherent governance framework to approach ethical, social-ecological, and technical aspects of geoengineering appears to be a promising step, Geoengineering Monitor believes that it will only be successful if the voices of women, peasant farmers, Indigenous peoples, trade unionists, and the poor have a firm seat at the technology assessment table. Otherwise, C2G2 and similar initiatives could easily end up as just a normalization exercise for geoengineering, dominated by those with a material interest in promoting technofix distractions at the expense of solutions that address the root causes of climate change and biodiversity loss.

On eve of Trump inauguration, White House report calls for geoengineering research

Photo: Wikipedia

The White House has released a report which for the first time recommends U.S. government-funded research into geoengineering. The report, which was submitted to Congress last week by the Office of Science and Technology Policy, falls short of calling for real-world experiments, laying out a case for research into the science behind large-scale climate intervention and the “possible consequences of any such measures.”

The White House report comes one week before businessman Donald Trump is set to be inaugurated as the 45th president of the United States. Trump has repeatedly denied the scientific consensus on climate change, and has nominated a collection of climate deniers to head key agencies related to energy, environment, and public lands in the U.S.

The report’s release raises the question of whether a Trump administration would support further research or even deployment of geoengineering technologies. There are a number of reasons to believe that he would.

First, Trump and his nominees are heavily linked to the fossil fuel industry, which has an enormous material interest – to the tune of trillions of dollars in booked assets – in promoting the notion that society can extract known carbon reserves and overshoot carbon budgets today, while relying upon future techno-fix solutions to clean up the mess later on.

The president-elect himself, as recently as 2015, was invested in Chevron, Statoil, Shell, Transcanada, and Energy Transfer Partners, the company behind the contested Dakota Access Pipeline. The list of Trump’s department nominees reads like a dystopian novel. If confirmed, the U.S. Energy Department, Environmental Protection Agency, and Department of the Interior would all be led by people with close ties to fossil fuel interests who deny anthropogenic climate change, while the State Department would be led by Rex Tillerson – longtime CEO of ExxonMobil.

The second point is that simultaneous support for climate change denial and geoengineering, or rapid shifts from one position to the other, are not logically incoherent when viewed through a political lens. This is particularly true among political actors on the far right, associated with groups ranging from the American Enterprise Institute, the Cato Institute, the Competitive Enterprise Institute, and the Heartland Institute.

Trump ally and former House speaker Newt Gingrich – who famously flipped from climate change skepticism, to geoengineering supporter, back to climate denial – offers just one prominent example of this maneuver. And it’s not difficult to imagine a similar shift from the president-to-be himself. Trump’s interview with the New York Times in November offers a window into his opportunist mode of thinking; where in response to a question about climate change, he notes that, “I have an open mind to it…we’re going to look very carefully,” followed immediately by, “it also depends on how much it’s going to cost our companies.”

The third point is that geoengineering is a technology particularly well-suited for those who fashion themselves as would-be autocrats. In a testament to the effectiveness of the U.N. Convention on Biological Diversity’s de-facto moratorium on geoengineering, the U.S. has so far restrained from proposing any real-world experiments. However, the U.S. is not a party to the convention – and it’s troublingly easy to imagine a Trump administration taking unilateral action on testing, or where feasible, deploying geoengineering technologies.

Much has been written about the possibility of a Trump administration utilizing large-scale disruption – such as a terrorist attack – as a pretense for suspending civil liberties, undermining democratic institutions, and going after political rivals. This age-old strategy, most recently on display in Erdogan’s Turkey following the attempted coup, provides a model for an authoritarian response to a cataclysmic natural disaster.

In fact, Trump’s practice of denigrating all sources of information outside of himself – ranging from the press, to political opposition, to the intelligence agencies – would prove particularly useful in declaring and sustaining activities under the banner of a climate state of emergency. Trump may not have to go it alone – with Rex Tillerson at the helm of the vast State Department apparatus, it’s likely Trump could find an ally in Putin’s Russia, which has at least on one occasion quietly pushed the IPCC to include geoengineering in its reports.

The antidote to all of this is to build and support organizations and movements united by a common vision of a fundamentally different type of economy – one that revolves around zero waste, ecosystem restoration, regional food systems, durable public housing and public transit, and community-scale renewable energy. An authoritarian approach to geoengineering will draw its power from fear and a recycled notion of “There Is No Alternative” type thinking – therefore our response must be based as much on hope and vision as it is on building organizations and movements with the power to win.

UN Convention still says “No” to manipulating the climate

Kevin Gill/Flickr CCby ETC Group

UN Convention on Biological Diversity reaffirms its moratorium on climate-related geoengineering

CANCUN, MEXICO – The UN Convention on Biological Diversity (CBD), which gathered at its 13th Conference of the Parties (COP 13) in Mexico from December 4-17, decided to reaffirm its landmark moratorium on climate-related geoengineering that it first agreed to in 2010.

Geoengineering refers to a set of proposed techniques that would intervene in and alter earth systems on a large scale – recently, these proposals have been gaining traction as a “technofix” solution to climate change. Examples include solar radiation management techniques such as blasting sulphate particles into the atmosphere as well as other earth systems interventions grouped under a second broad umbrella of ‘carbon dioxide removal.’

The reaffirmation of the CBD moratorium is even more relevant in the light of the Paris Agreement on climate change, in which governments agreed to limit global temperature rise to 1.5 degrees. Geoengineers quickly interpreted the Paris Agreement as allowing or encouraging geoengineering to meet that ambitious goal.

“The decision to reaffirm the global moratorium on geoengineering is an important message for those who are now promoting it as shortcut to achieve the Paris Agreement goals. Geoengineering schemes will impact the global commons and will have transboundary impacts that could be worse than climate change,” said Silvia Ribeiro, Latin America Director of ETC Group. “The CBD made a landmark decision on 2010 to halt the deployment of geoengineering because of its potential widespread negative impacts on people and biodiversity, and that decision holds firm.”

“Climate change and biodiversity erosion are both acute interrelated global problems that demand urgent attention and action,” said Neth Daño, Asia Director of ETC Group. “However, climate geoengineering proposals are a set of unproven techno-fixes that do not address the root causes of either climate change or biodiversity loss, and could deviate attention and resources from real, affordable, safe, and globally much more fair alternatives.”

The CBD decision noted also that the potential impacts of geoengineering on biodiversity and ecosystem functions, as well as on socio-economic and cultural/ethical issues have not been studied. This is one of the main conclusions in the updated report on the impacts on geoengineering on biodiversity that was organized by the CBD. “Taking the precautionary approach is the least the UN can do,” said Silvia Ribeiro.

In a 2016 article in Nature, Phil Williamson, the coordinator of that report, highlighted that the Intergovernmental Panel on Climate Change, which released the largest climate change report to date in 2014, “[…] leaves out one crucial consideration: the environmental impacts of large-scale CO2 removal. This omission is striking because the set of IPCC emissions scenarios that are likely to limit the increase in global surface temperature to 2C by 2100 […] mostly relies on large-scale CO2 removal.”[i]

Specifically, the IPCC did not look at the environmental or biodiversity impacts of their favoured technique: BECCS (bioenergy with carbon capture and storage) or of other so called “negative emissions” technologies. Furthermore, recent scientific studies also show that these proposals are not technically or economically viable, but would imply large impacts on biodiversity and traditional livelihoods.[ii]

“The reaffirmation of the CBD moratorium on geoengineering, taken by consensus of 196 governments, is a wake-up call for the governments considering these dangerous proposals” said Jim Thomas, Programme Director at ETC Group. “It was a mature decision not only to protect biodiversity, but also to prevent the few and powerful actors that want geoengineering from taking control of the global thermostat.”

The decision also emphasised that indigenous peoples and local communities’ knowledge must be taken into account. “There are plenty of proven viable, sustainable, culturally and economically viable solutions to stop both the erosion of biodiversity and climate change, such as peasant agriculture, that need attention and support instead of high-tech, high-risk false solutions such as geoengineering” said Silvia Ribeiro.

Geoengineering has been a topic of discussion in the CBD for almost a decade and in 2008, the CBD issued a moratorium on ocean fertilization. Therefore, the geoengineering decision in COP 13 was preceded by longer debates in the CBD’s subsidiary scientific body (SBSTTA) and previous COPs creating high level of agreement, and as such was not a hotly debated topic in Cancun.

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Note to editors:

The full decision of the CBD can be found here: https://www.cbd.int/doc/meetings/cop/cop-13/in-session/cop-13-l-04-en.pdf

An eight-page briefing on geoengineering and the CBD can be found here: http://www.etcgroup.org/sites/www.etcgroup.org/files/files/final_geoengineering_brief_cop_13_web.pdf

Expert Contacts:

Silvia Ribeiro: +52 1 55 2653 3330, silvia@etcgroup.org

Neth Dano: +63 917 532 9369, neth@etcgroup.org

Jim Thomas: +1 (514) 516-5759, jim@etcgroup.org

Communications Contact:
Trudi Zundel: +1 (226) 979-0993, trudi@etcgroup.org

[i] Williamson, Phil. “Emissions reduction: Scrutinize CO2 removal methods.” Nature. 530, no. 7589 (2016): 153. http://www.nature.com/news/emissions-reduction-scrutinize-co2-removal-methods-1.19318

[ii] Kevin Anderson and Glen Peters, “The trouble with negative emissions.” Science, October 2016.

Almuth Ernsting and Oliver Munnion, “Last Ditch Climate Option or Wishful Thinking? Bioenergy with Carbon Capture and Storage.” Biofuelwatch report, November 2015. http://www.wri.org/publication/avoiding-bioenergy-competition-food-crops-and-land

Tim Searchinger and Ralph Heimlich, “Avoiding Bioenergy Competition for Food Crops and Land.” January 2015. Creating a Sustainable Food Future, Installment Nine. http://www.nature.com/news/emissions-reduction-scrutinize-co2-removal-methods-1.19318

 

UN to extend freeze on climate change geoengineering

Iron fertilization involves dumping iron-rich soil into the ocean. Scientists say iron-rich dirt promotes the growth of plankton, microscopic organisms that provide a food source for salmon and other sealife. (CBC/HSRC)
Geoengineering proposals include iron fertilization, involving dumping iron-rich soil into the ocean (CBC/HSRC)

Update to this article: The plenary of the COP 13 adopted the decision described below on Friday 9th December

By Ed King (Climate Home)

Draft documents suggest countries will agree to further ban on large-scale climate techno-fixes, warning risks of damage to biodiversity outweigh potential benefits

Countries should resist the urge to experiment with large scale planetary geoengineering until it’s clear what the consequences of meddling with the oceans or atmosphere may be.

That’s the nub of a decision expected to be taken at the UN’s biannual biodiversity summit taking place in Cancun, Mexico this week, emphasising a “precautionary approach” to such projects.

With greenhouse gas emissions closing in on levels that could guarantee warming of 1.5C above pre industrial levels and an El Nino-boosted 2016 likely to be the hottest year on record, some scientists are looking to emergency measures.

But the UN is sticking to a familiar line: pumping the atmosphere with tiny mirrors to deflect sunlight, boosting the uptake of CO2 in oceans by stimulating plankton growth, or burning wood and pumping the emissions underground could be a bad idea.

“We’re concerned that with any initiative regarding the use of geoengineering there needs to be an assessment,” UN biodiversity chief Braulio Ferreira de Souza Dias told Climate Home.

“These can have unforeseen results and spin-offs. If you capture carbon in the oceans, this is effective through all the food chains.”

Even national risk assessments on individual geoengineering projects would still form an “incomplete basis for global regulation” says the latest iteration of the UN draft decision, echoing previous Convention on Biological Diversity (CBD) decisions in 2010, 2012 and 2014.

“More trans-disciplinary research and sharing of knowledge among appropriate institutions is needed,” it says, citing potential impacts on ecosystems and potential ethical issues.

For instance, one study by scientists at the UK Met Office in 2013 said the release of fine particles into the northern hemisphere atmosphere could lower temperatures, but heighten drought risk in the Sahel.

Still, Bristol University academic Matt Watson – one of the UK’s top geoengineering researchers – told Climate Home there are still a “range of experiments that would not have any effect on biodiversity”.

“We are not doing a great job of protecting biodiversity now (the IPCC’s projections are truly terrifying) – how will we know if geoengineering would exacerbate (or reduce) impacts on biodiversity unless we research it?” he said in an email.

That view was echoed by Richard Darton, co-director of the Oxford Geoengineering Programme, who said controlled tests allowed under CBD rules should continue “to verify the science and engineering” but that more research was inevitable given the scale of warming

“Whilst I thoroughly agree that we can best cut anthropogenic emissions as the best way to manage climate change, the CBD will have to face the fact that it simply isn’t happening fast enough,” he said.

“Learning more about geoengineering is absolutely necessary. At the moment we have the bizarre circumstance that climate scenarios which will meet 2C assume BECCS [bioenergy with carbon capture and storage] will be applied on a very big scale – an assumption at odds with the resolution of CBD apparently.

“We simply must explore BECCS and all the other techniques to understand what (if anything) they can do for us, and what the entire earth-system and human-system impacts might be.”

The last publicised large-scale geoengineering trial took place in 2012 when a US businessman dumped tonnes of iron filings into the sea off Canada, in violation of the UN moratorium.

The aim was to suck carbon from the atmosphere by stimulating the growth of plankton which would then die and sink to the ocean floor, thus sequestering the CO2.

In 2013, leaked documents revealed Russia pushed for the UN’s climate science body to support the potential of geoengineering to lower global temperatures in its major AR5 climate report.

In the event the the Intergovernmental Panel on Climate Change (IPCC) study did cover geoengineering, warning of “numerous uncertainties, side effects and risks” of efforts to manage solar radiation.

Since then, information on other programmes has been thin. Germany is conducting indoor experiments while the UK government recently stumped up £8·3 million (US$10.5m) for research into technologies to suck carbon dioxide from the atmosphere.

Policy inertia

The UN CBD draft decision notes “very few countries” have provided “information on measures they have undertaken”.

Poor reporting and the lack of debate around the issue are a concern, said Andrew Light, a former US senior state department climate official and a professor at George Mason University, who interpreted the CBD text as a “plea” rather than a ban.

“If we are ever to have a conversation about governance we need to normalise reporting,” he told Climate Home, suggesting this would be a first step before out-of-laboratory experiments are authorised.

“We need to be looking into the full range of activities, especially when we’re talking about the need to move towards net decarbonisation by 2050 or thereafter.”

“Countries have not provided information because they are not talking about it,” said Janos Pasztor, climate advisor to outgoing UN secretary general Ban Ki-moon and head of the Carnegie Climate Geoengineering Governance Project.

“There is practically no discussion at a policy level – it’s a big gap and we need to shift the debate.”

Using forests to curb climate change threatens human rights

rainforest
Kim Seng/Flickr CC

by Fred Pearce (Thomson Reuters Foundation News)

Trees offer ways to help achieve “negative emissions”, but what does that mean for forest communities?

The 2015 Paris Agreement on climate change was a landmark the world rightly applauded. Its pledge to limit global warming to well below 2 degrees Celsius – and preferably 1.5 degrees – lays down one of humanity’s greatest challenge for the 21st century. But how to achieve it?

Climate scientists say it is almost an impossible task if we only rely on reducing emissions from our power stations, transport systems and factories.  Even ending deforestation will be insufficient. They say we will have to find ways of removing carbon dioxide from the atmosphere: “negative emissions” in the climate-change jargon.

There are many schemes for how do this using chemistry and geology, but some are wildly expensive and others are not yet feasible. The most likely current option though, is giving terrestrial plants such as trees or bioenergy crops a helping hand in photosynthesising more CO2 from the air.

Here are the four main proposals for how this could be done, and their implications – which until now have barely been considered:

1. Sink forests: The most straightforward method of removing CO2 from the atmosphere is to boost nature’s primary terrestrial carbon store, by creating giant “carbon sink” forests to permanently hold carbon in timber and soil.

To assure these forests did their job, there would have to be a programme to maintain their carbon-holding power as they age and trees die. A critical question is how permanent these carbon sinks could be in the face of inevitable climate change. They could succumb to droughts or migrating pests – potentially releasing their carbon stores into the atmosphere and turbo-charging climate change.

One huge potential drawback is that calculations to date suggest that planting enough trees to soak up and store 500 billion tonnes of CO2 before the end of the century would likely require around 10 million square kilometres of land. That is an area the size of the Sahara or the US.

2. Bioenergy forests: Rather than trying to create carbon-sink forests that hold carbon forever, an alternative is to make productive use of them, by harvesting the timber and burning it in power stations as a substitute for fossil fuels. Provided the burned trees are replaced by new ones, the CO2 emissions from burning would be neutralised by the regrowth. That’s the theory, anyhow.

Would it work in practice? The best place to look is where bioenergy is already used as a strategy for reducing CO2 emissions. The European Union already incentivises biomass burning in power plants and heating systems. Almost half of harvested timber in the EU is now used for the generation of electricity or heating.

It has led to a boom in industrial forestry. Yet, worryingly, countries that rely most on biomass for energy, such as Slovakia and Romania, have the least credible systems for ensuring that harvested trees are replaced. Without that obligation, the idea that the fuel is renewable or carbon-neutral is a sham.

“You could cut down the Amazon, turn it into a parking lot, ship the trees to Europe to replace coal, and Europe would claim a reduction in emissions,” argues Tim Searchinger of Princeton University.

The presumed carbon-neutrality of biomass forests ignores the time lag involved.  Burning trees in a power station results in the immediate mass release of their carbon in the form of CO2. But the replacement trees only soak up the equivalent amount of CO2 gradually, as they grow.

There are therefore serious questions about the sustainability and carbon credentials of bioenergy in its current form.

3. BECCS: The third proposal for turning forests into a way of generating negative emissions is, for many climate scientists the Holy Grail. It involves combining bioenergy forests with technology being developed for capturing CO2 going up the power station stack and then burying it out of harm’s way – for instance in old salt mines or abandoned oil wells. This is known as Carbon Capture and Storage.

In the complete system, known as Biomass with Carbon Capture and Storage Carbon (BECCS), carbon is captured from the air by growing trees, burned to generate energy and then buried. In theory, the more energy is generated, the more CO2 is sucked out of the air.

BECCS is a better use of land than permanent carbon-sink forests, say its advocates, because harvested trees can be replaced with new trees. And it is better than normal bioenergy because it avoids emissions from power stations. So every time the land set aside for trees is replanted, more carbon can be captured, doubling up on the negative emissions. If two growing cycles could be accomplished by the end of the century, then the amount of land needed to capture 500 billion tonnes by 2100 could be halved to maybe 5 million square kilometres.

No BECCS project is yet in operation. And while the basic technology is used on a small scale in the oil industry, the idea of doing it on a huge scale, as a continuous process that remove emissions from major power plants across the world, raises huge questions about its practicability and sustainability.

Whatever the carbon gains from negative-emissions technologies, they have to exist in a world of competing demand for – and rights to – land. And converting land into carbon-sink forests would involve a land grab on a scale never seen before: a human rights calamity, with major implications for food security and biodiversity.

Looked at from the forests, this appears neither green nor renewable. It seems like a recipe for the industrialisation of environmentalism, with vast swathes of the world’s most diverse forest ecosystems turned into barren carbon factories – and their inhabitants into, at best, factory hands.

A new approach is required. One based not on creating a vast new industry for sucking carbon from the air, but on reinstating nature’s ability to store carbon in a landscape also occupied by humans – which leads us to the last of the four current options for creating carbon sinks:

4. Natural regeneration: Properly conceived, many argue, reinstating natural ecosystems could play a huge role in negative emissions, without riding roughshod over other global priorities. The Stockholm Environment Institute recently concluded that simply allowing former natural forests and degraded forest areas to regrow could lock up some 330 billion tonnes of CO2.

There are plenty of examples already of what this could mean. Twenty-five years ago, Guatemala created the Maya Biosphere Reserve. The aim was to protect the largest remaining tropical rainforest in Central America. At the time, conservationists were angry that government officials set up a dozen zones inside the reserve where local communities could do small-scale logging.

Today that seems like a stroke of genius. The forests in the core protected areas of the reserve are rapidly being lost, as cattle ranchers invade. But the community forests, jealously guarded by locals, thrive. Their deforestation rates are only 5 percent of those in the supposedly “protected” areas. On current trends, 40 percent of the reserve will be stripped of forests by 2050, and most of what survives will be in the community-run areas.

There is a lesson here for those who seek to commandeer the world’s forests as carbon sinks. Community consent is not just vital; it is the touchstone for success.

Fred Pearce’s new report for Fern on negative emissions technologies is called Going Negative – How carbon sinks could cost the Earth.

Radical Realism About Climate Change

UniversityBlogSpot/Flickr CC by Lili Fuhr (Project Syndicate)

BERLIN – Mainstream politics, by definition, is ill equipped to imagine fundamental change. But last December in Paris, 196 governments agreed on the need to limit global warming to 1.5°C above pre-industrial levels – an objective that holds the promise of delivering precisely such a transformation. Achieving it will require overcoming serious political challenges, reflected in the fact that some are advocating solutions that will end up doing more harm than good.

One strategy that has gained a lot of momentum focuses on the need to develop large-scale technological interventions to control the global thermostat. Proponents of geo-engineering technologies argue that conventional adaptation and mitigation measures are simply not reducing emissions fast enough to prevent dangerous warming. Technologies such as “carbon capture and storage” (CCS), they argue, are necessary to limit damage and human suffering.

The Intergovernmental Panel on Climate Change seems to agree. In its fifth assessment report, it builds its scenarios for meeting the Paris climate goals around the concept of “negative emissions” – that is, the ability to suck excess carbon dioxide out of the atmosphere.

But this approach ignores serious problems with the development and deployment of geo-engineering technologies. Consider CCS, which is the process of capturing waste CO2 from large sources like fossil-fuel power plants and depositing it in, say, an underground geological formation, thereby preventing it from entering the atmosphere.

It sounds good. But what makes it economical is that it enables enhanced oil recovery. In other words, the only way to make CCS cost-effective is to use it to exacerbate the problem it is supposed to address.

The supposed savior technology – bioenergy with carbon capture and storage (BECCS) – is not much better. BECCS begins by producing large amounts of biomass from, say, fast-growing trees which naturally capture CO2; those plants are then converted into fuel via burning or refining, with the resulting carbon emissions being captured and sequestered.

But bioenergy is not carbon neutral, and the surge in European demand for biomass has led to rising food commodity prices and land grabs in developing countries. These realities helped persuade the scientists Kevin Anderson and Glen Peters recently to call carbon removal an “unjust and high-stakes gamble.”

What about other geo-engineering proposals? Solar Radiation Management (SRM) aims to control the amount of sunlight that reaches the Earth, essentially mimicking the effect of a volcano eruption. This may be achieved by pumping sulphates into the stratosphere or through “marine cloud brightening,” which would cause clouds to reflect more sunlight back into space.

But blasting sulphates into the stratosphere does not reduce CO2 concentrations; it merely delays the impact for as long as the spraying continues. Moreover, sulphate injections in the northern hemisphere could cause serious drought in the Africa’s Sahel region, owing to dramatic reductions in precipitation, while some African countries would experience more precipitation. The effect on the Asian monsoon system could be even more pronounced. In short, SRM could severely damage the livelihoods of millions of people.

If geo-engineering can’t save us, what can? In fact, there are a number of steps that can be taken right now. They would be messier and more politically challenging than geo-engineering. But they would work.

The first step would be a moratorium on new coal mines. If all currently planned coal-fired power plants are built and operated over their normal service life of 40 years, they alone would emit 240 billion tons of CO2 – more than the remaining carbon budget. If that investment were re-allocated to decentralized renewable-energy production, the benefits would be enormous.

Moreover, with only 10% of the global population responsible for almost 50% of global CO2 emissions, there is a strong case to be made for implementing strategies that target the biggest emitters. For example, it makes little sense that airlines – which actually serve just 7% of the global population – are exempt from paying fuel taxes, especially at a time when ticket prices are at an historic low.

Changes to land use are also needed. The 2009 International Assessment of Agricultural Knowledge, Science and Technology for Development charts the way to a transformed agricultural system – with benefits that extend far beyond climate policy. We must apply this knowledge around the world.

In Europe, the waste sector could make a significant contribution to a low-carbon economy. Recent research, commissioned by Zero Waste Europe, found that optimal implementation of the European Commission’s “circular economy package” waste targets could save the European Union 190 million tons of CO2 per year. That is the equivalent of the annual emissions of the Netherlands!

Available measures in the transport sector include strengthening public transportation, encouraging the use of railways for freight traffic, building bike paths, and subsidizing delivery bicycles. In Germany, intelligent action on transport could reduce the sector’s emissions by up to 95% by 2050.

Another powerful measure would be to protect and restore natural ecosystems, which could result in the storage of 220-330 gigatons of CO2 worldwide .

None of these solutions is a silver bullet; but, together, they could change the world for the better. Geo-engineering solutions are not the only alternatives. They are a response to the inability of mainstream economics and politics to address the climate challenge. Instead of trying to devise ways to maintain business as usual – an impossible and destructive goal – we must prove our ability to imagine and achieve radical change.

If we fail, we should not be surprised if, just a few years from now, the planetary thermostat is under the control of a handful of states or military and scientific interests. As world leaders convene for the 22nd United Nations Framework Convention on Climate Change to bring the Paris agreement into force, they should repudiate geo-engineering quick fixes – and demonstrate a commitment to real solutions.

With Sights Set on COP22, Group Offers Roadmap for ‘Fair Future’ in Warming World

by Nika Knight (Common Dreams)

A sustainable solution to the climate crisis will also work to alleviate poverty and seek climate justice, says Friends of the Earth Germany

“A future without climate chaos for all human beings on our planet is only possible if we don’t pin our hopes on large-scale technologies. Instead, we have to make sure that the energy and agricultural transitions are being pushed forward as fast as possible,” said Heinrich Böll Foundation president Barbara Unmüßig

An illustration from the report by Friends of the Earth Germany
An illustration from the report by Friends of the Earth Germany

At the upcoming United Nations climate conference in Morocco, negotiations for how to fulfill COP21‘s agreement to limit global warming to 1.5º Celsius must emphasize methods that will also alleviate poverty and climate injustice, rather than leaning on “questionable technologies” such as geoengineering and carbon offset, says Friends of the Earth (FOE) Germany.

“We cannot count on unproven, costly, and ecologically risky negative emission technologies to save us from climate chaos.”
—Hubert Weiger,
Friends of the Earth Germany

That’s the argument put forth in the group’s new report, “A change of course: How to build a fair future in a 1.5 degree world” (pdf, in German), published Friday alongside the German Catholic Bishops’ Organisation for Development Cooperation (MISEREOR) and the Heinrich Böll Foundation.

The climate conference will take place in Marrakech, Morocco, from November 7-18.

The report takes aim at popular so-called “negative emissions” technologies, such as geoengineering, carbon offset regimes, and bioenergy with carbon capture and storage (BECCS), arguing that leaders must pursue true sustainability instead.

“The fatal flaw of all negative emissions technology proposals is this: The hope for an atmospheric line of credit allows today’s urgent need for radical reductions in CO2 emissions to fall by the wayside,” the report argues. “What’s currently Plan B is in fact the best way to force Plan A into the background—a fundamentally different economy, one that preserves the planet for all forms of life.”

Instead of such “questionable technologies,” the report argues for policies that have poverty reduction and climate justice as their central focus.

“In reaction to the Paris Agreement, we need to phase out coal, speed up the transition to renewables, phase out combustion engines, and protect and restore forests and soils,” explained Hubert Weiger, chairman of Friends of the Earth Germany, in a statement.

“It is crystal clear that effective climate protection and equitable, sustainable development can only be considered together,” added Heinrich Böll Foundation president Barbara Unmüßig. “A future without climate chaos for all human beings on our planet is only possible if we don’t pin our hopes on large-scale technologies. Instead, we have to make sure that the energy and agricultural transitions are being pushed forward as fast as possible. Technological fixes such as geoengineering are betting on future possibilities such as sucking CO2 from the atmosphere or keeping sunlight away from the Earth. This is a dangerous distraction from the necessary steps that we can already implement today. The coming-into-force of the Paris Agreement asks for exactly this change in course.”

“As northern countries that have caused the climate catastrophe, we need to lead by example,” Weiger continued. “We cannot count on unproven, costly, and ecologically risky negative emission technologies to save us from climate chaos. If we postpone implementing the traditional climate mitigation solutions, we will miss the rapidly closing window of opportunity to limit global warming to 1.5 degrees.”

Indeed, new research has shown that the goal to limit warming to 1.5º is already a long-shot.

“The vague hope that we could all survive in a world that is 3 degrees warmer than before industrialization is deceptive,” said Pirmin Spiegel, director general of MISEREOR. “It is our responsibility to safeguard the lives of millions of people by limiting global warming to 1.5 degrees. This is not only a technological challenge; instead, it has widespread societal and cultural implications that we all have to face.”

The trouble with negative emissions

By Kevin Anderson and Glen Peters (Science)

Reliance on negative-emission concepts locks in humankind’s carbon addiction

In December 2015, member states of the United Nations Framework Convention on Climate Change (UNFCCC) adopted the Paris Agreement, which aims to hold the increase in the global average temperature to below 2°C and to pursue efforts to limit the temperature increase to 1.5°C.

The Paris Agreement requires that anthropogenic greenhouse gas emission sources and sinks are balanced by the second half of this century. Because some nonzero sources are unavoidable, this leads to the abstract concept of “negative emissions”, the removal of carbon dioxide (CO2 ) from the atmosphere through technical means. The Integrated Assessment Models (IAMs) informing policy-makers assume the large-scale use of negative-emission technologies. If we rely on these and they are not deployed or are unsuccessful at removing CO2 from the atmosphere at the levels assumed, society will be locked into a high-temperature pathway.

CARBON BUDGETS

To understand the implications of the Paris Agreement for mitigation policy, we must translate its qualitative temperature limits into quantitative carbon budgets, specifying how much CO2 can be emitted across the remainder of the century to keep warming below a given temperature level (1). Uncertainties in the climate system mean that such budgets are specified with quantitative likelihoods.

Borrowing from the taxonomy of likelihoods used by the Intergovernmental Panel on Climate Change (IPCC), the most generous interpretation of the Paris Agreement’s requirement to keep the temperature rise well below 2°C is, at least, a likely (66 to 100%) chance of not exceeding 2°C.

The IPCC has assessed 900 mitigation scenarios from about 30 IAMs (2). Of these, 76 scenarios from five IAMs had sufficient data to estimate the carbon budget for a likely chance of not exceeding 2°C. These scenarios give a carbon budget of between 600 and 1200 billion metric tons (Gt) CO 2 (10 to 90% range) for the period from 2016 until the peak in temperature [updated from (1)]. Increasing the likelihood of keeping temperatures below 2°C (or shifting the ceiling to 1.5°C) will reduce still further the available carbon budget (3). The budget is also subject to a reduction each year, currently around 40 Gt CO 2 , due to continued fossil fuel, industry, and land-use change emissions.

It is important to keep in mind that despite their intuitive appeal, the complexity of carbon budgets make it impossible to assign a specific budget to a given temperature rise.

anderson-graphFROM BUDGETS TO EMISSION PATHWAYS

Because the carbon budgets represent cumulative emissions, different emission pathways can be consistent with a given budget. Using the 76 scenarios consistent with a likely chance of not exceeding 2°C (see the figure), two key features are immediately striking. First, the scenarios assume that the large-scale rollout of negative-emission technologies is technically, economically, and socially viable (2, 4). In many scenarios, the level of negative emissions is comparable in size with the remaining carbon budget (see the figure) and is sufficient to bring global emissions to at least net zero in the second half of the century.

Second, there is a large and growing deviation between actual emission trends and emission scenarios. The sum of the national emission pledges submitted to the Paris negotiations (COP21) lead to an increase in emissions, at least until 2030. They thus broaden the division between pathways consistent with the temperature goals of the Paris Agreement (5) and require either much more severe near-term mitigation (6) or additional future negative emissions.

It is not well understood by policy-makers, or indeed many academics, that IAMs assume such a massive deployment of negative-emission technologies. Yet when it comes to the more stringent Paris obligations, studies suggest that it is impossible to reach 1.5°C with a 50% chance without significant negative emissions (3). Even for 2°C, very few scenarios have explored mitigation without negative emissions (2).

Negative emissions are also prevalent in scenarios for higher stabilization targets (7). Given such a pervasive and pivotal role of negative emissions in mitigation scenarios, their almost complete absence from climate policy discussions is disturbing and needs to be addressed urgently.

NEGATIVE-EMISSION TECHNOLOGIES

Negative-emission technologies exist at various levels of development (8–11). Afforestation and reforestation, although not strictly technologies, are already claimed by countries as mitigation measures. Bioenergy, combined with carbon capture and storage (BECCS), is the most prolific negative-emission technology included in IAMs and is used widely in emission scenarios. It has the distinct feature of providing energy while also, in principle (12), removing CO2 from the atmosphere. Assuming that carbon is valued, BECCS can thus provide an economic benefit that may offset, at least in part, the additional costs of using the technology (13). Generally, carbon is assumed to be fully absorbed during biomass growth, captured before or after combustion, and then stored underground indefinitely. Despite the prevalence of BECCS in emission scenarios at a level much higher than afforestation, only one large-scale demonstration plant exists today.

Other negative-emission technologies have not moved beyond theoretical studies or small-scale demonstrations. Alternative and adjusted agricultural practices, including biochar, may increase carbon uptake in soils (9). It may also be possible to use direct air capture to remove CO2 from the atmosphere via chemical reactions, with underground storage similar to CCS. Enhancing the natural weathering of minerals (rocks) may increase the amount of carbon stored in soils, land, or oceans. Introduction of biological or chemical catalysts may increase carbon uptake by the ocean. New technologies, designs, and refinements may emerge over time.

BECCS: A POLITICAL PANACEA

The allure of BECCS and other negative-emission technologies stems from their promise of much-reduced political and economic challenges today, compensated by anticipated technological advances tomorrow. Yet there are huge opportunities for near-term, rapid, and deep reductions today at little to modest costs, such as improving energy efficiency, encouraging low-carbon behaviors, and continued deployment of renewable energy technologies. Why, then, is BECCS used so prolifically in emission scenarios?

The answer is simple. Integrated assessment models often assume perfect knowledge of future technologies and give less weight to future costs. In effect, they assume that the discounted cost of BECCS in future decades is less than the cost of deep mitigation today. In postponing the need for rapid and immediate mitigation, BECCS licenses the ongoing combustion of fossil fuels while ostensibly fulfilling the Paris commitments.

The idea behind BECCS is to combine bioenergy production with CCS, but both face major and perhaps insurmountable obstacles. Two decades of research and pilot plants have struggled to demonstrate the technical and economic viability of power generation with CCS, even when combusting relatively homogeneous fossil fuels (14). Substituting for heterogeneous biomass feedstock adds to the already considerable challenges.

Moreover, the scale of biomass assumed in IAMs—typically, one to two times the area of India—raises profound questions (10) about carbon neutrality, land availability, competition with food production, and competing demands for bioenergy from the transport, heating, and industrial sectors. The logistics of collating and transporting vast quantities of bioenergy—equivalent to up to half of the total global primary energy consumption—is seldom addressed. Some studies suggest that BECCS pathways are feasible, at least locally (15), but globally there are substantial limitations (10). BECCS thus remains a highly speculative technology.

Although BECCS, like all negative-emission technologies, is subject to scientific and political uncertainties, it dominates the scenario landscape. Yet, as recognition of the ubiquitous role of BECCS in mitigation scenarios has grown, so have concerns about its deployment (10, 11). Its land-use impacts could include terrestrial species losses equivalent to, at least, a 2.8°C temperature rise (11), leading to difficult trade-offs between biodiversity loss and temperature rise. There is also little robust analysis of the trade-offs between large-scale deployment of BECCS (and all negative-emission technologies) and the Sustainable Development Goals (SDGs). But such a level of caution is far removed from the technical utopia informing IAMs. Despite BECCS continuing to stumble through its infancy, many scenarios assessed by the IPCC propose its mature and large-scale rollout as soon as 2030 (see the figure).

MORAL HAZARD AND INEQUITY

The appropriateness or otherwise of relying, in significant part, on negative-emission technologies to realize the Paris commitments is an issue of risk (7). However, the distribution of this risk is highly inequitable. If negative-emission technologies fail to deliver at the scale enshrined in many IAMs, their failure will be felt most by low-emitting communities that are geographically and financially vulnerable to a rapidly changing climate.

The promise of future and cost-optimal negative-emission technologies is more politically appealing than the prospect of developing policies to deliver rapid and deep mitigation now. If negative-emission technologies do indeed follow the idealized, rapid, and successful deployment assumed in the models, then any reduction in near-term mitigation caused by the appeal of negative emissions will likely lead to only a small and temporary overshoot of the Paris temperature goals (3). In stark contrast, if the many reservations increasingly voiced about negative-emission technologies (particularly BECCS) turn out to be valid, the weakening of near-term mitigation and the failure of future negative-emission technologies will be a prelude to rapid temperature rises reminiscent of the 4°C “business as usual” pathway feared before the Paris Agreement (5).

Negative-emission technologies are not an insurance policy, but rather an unjust and high-stakes gamble. There is a real risk they will be unable to deliver on the scale of their promise. If the emphasis on equity and risk aversion embodied in the Paris Agreement are to have traction, negative-emission technologies should not form the basis of the mitigation agenda. This is not to say that they should be abandoned (14, 15). They could very reasonably be the subject of research, development, and potentially deployment, but the mitigation agenda should proceed on the premise that they will not work at scale.

The implications of failing to do otherwise are a moral hazard par excellence.

REFERENCES AND NOTES

1. J. Rogelj et al., Nat. Clim. Change 6, 245 (2016).
2. L. Clarke et al., in Climate Change 2014: Mitigation of Climate Change. Contribution of Working Group III to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, O. Edenhofer et al., Eds. (Cambridge Univ. Press, Cambridge/New York, 2014), pp. 413–510.
3. J. Rogelj et al., Nat. Clim. Change 5, 519 (2015).
4. H. J. Buck, Clim. Change 10.1007/s10484-016-1770-6 (2016).
5. J. Rogelj et al., Nature 534, 631 (2016).
6. K. Anderson, Nat. Geosci. 8, 898 (2015).
7. S. Fuss et al., Nat. Clim. Change 4, 850 (2014).
8. M. Tavoni, R. Socolow, Clim. Change 118, 1 (2013).
9. P. Smith, Glob. Change Biol. 22, 1315 (2016).
10. P. Smith et al., Nat. Clim. Change 6, 42 (2015).
11. P. Williamson, Nature 530, 153 (2016).
12. A. Gilbert, B. K. Sovacool, Nat. Clim. Change 5, 495 (2015).
13. D. L. Sanchez et al., Nat. Clim. Change 5, 230 (2015).
14. D. M. Reiner, Nat. Energy 1, 15011 (2016).
15. D. L. Sanchez, D. M. Kammen, Nat. Energy 1, 15002 (2016).
16. The figure shows the median of the 76 IPCC scenarios that limit the global temperature rise to 2°C with 66% likelihood (2). Realized negative emissions are estimated by converting the BECCS energy consumption [exajoules (EJ) per year], assuming an average biomass emission factor of 100 metric tons of CO 2 per terajoule (TJ) and assuming that 90% of the CO 2 is captured. The emission pledges (INDCs) in 2030 are estimated based on cumulative emissions from 2011 to 2030 (5).